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Re: Re: TX-Cycle Recommendation?




> 
> Ahh...  Why is the packet a duplex freq?  Since I am not running APRS,
> only beaconing my posistion, I really don't care about RXing the ISS,
> just TXing through it.  If I make it, I'll see myself on ariss.net.  So,
> I just changed my radio to 145.99 simplex.  The only other stations I'll
> hear are local ones, but if collisions are my problem for now, this
> should help out somewhat.
> 
> Jamie
> 
> Margaret Leber wrote:
> >
> > Mark Fellhauer wrote:
> >
> >  > Really?  I can't say as my obervations have been the same.   I'm hearing
> >  > wide gaps between downlink packets and maybe seeing 4 callsigns per
> >  > pass.  As opposed to Sunsat or Mir, it's very quiet.
> >
> > Yes, that what I hear too.
> >
> > But I'm inferring that silence on the downlink implies chaos on the
> > uplink. Since we're "working split", you can't *hear* all the collisions
> > that are happening on the uplink. In fact, you'd have to be on-board
> > Alpha to hear all that crap. The silent intervals represent the time
> > when the ISS digi couldn't pull a coherent packet out of all that noise.
> >
> > Worse yet, the transmitting stations can't hear each other either...they
> > can't wait for the other carrier to drop because there *is* no other
> > carrier on the frequency they're listening to.
> >
> > Ever use VHF AM in a light aircraft? Things (like say on 122.8 MHz on a
> > nice saturday morning) are always quiet on the ground; you only hear
> > aircraft that are on your frequency, and in your sky.
> >
> > Then once you're aloft--say up 2,000' or so--you hear
> > *everybody*...every aircraft *and* ground station within a 50 mile
> > radius or so is now line-of-sight to you. And the ones that are at a low
> > altitude or on the ground don't *know* when they're blocking each other
> > from your point-of-view...so you get a headset full of heterodyne a lot
> > of the time.
> >
> > 73 de Maggie K3XS
> >
> 
> --
> 
> A windoze-free computer
> SuSE Linux / KDE

-- 

A windoze-free computer
SuSE Linux / KDE
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